An electrical discharge machining process (EDM) makes it possible to remove material from a workpiece and thus drill a hole in such workpiece. In such electroerosive machining of the workpiece, an electrical field is applied between an electrode and a machining location of the workpiece; in addition, a suitable machining fluid is supplied to this machining location.
In International Patent Application WO 03/041900 A2, an EDM method including magnetic gap regulation is discussed. In this method, a stationary magnetic field regulates a distance between the electrode and the machining location of the workpiece. The electrode is designed as a current-carrying conductor and is situated within the magnetic field. Due to a Lorentz force induced by the magnetic field and acting on the conductor, this conductor is deflected within a vertically positioned sleeve guide so that it performs an axial movement. This produces an optimal distance between the electrode and the workpiece as a function of the flowing current. The greater this current, the greater is the Lorentz force acting upon the conductor and an associated deflection. The distance of one end of the conductor from the workpiece is thus in direct proportion to the current flowing through the conductor.